Idler for driving-belts



(NQModeL) A. V. HALL & W. S. HOLMES.

IDLBR FOR DRIVING BELTS.

No. 487,564. Patented Dec. 6, 1892."

WJZWESSES )QQ. W 9 $122 ney s UNirE STATES PATENT OFFICE.

ALEXANDER V. HALL AND WILLIAM S. HOLMES, OF BATON ROUGE, LOUISIANA.

IDLER FOR DRIVING-BELTS.

SPECIFICATION forming part of Letters Patent No. 487,564, dated December 6, 1892.

Application filed August 13, 1892. Serial No. 442,949. (No model.)

To all whom it may concern:

Be it kn own that we, ALEXANDER V. HALL and WILLIAM S. HOLMES, of Baton Rouge, in the parish of East Baton Rouge and State of Louisiana, have invented certain new and useful Improvements in Idlers for Driving-Belts; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

Our invention relates to a new and improved idler for driving-belts, and has for its object to provide a device that will automatically maintain a regular and even tension upon the belt and take up any slack that may occur therein and to provide means for throwing the tension upon either side of the belt to prevent the same from running off the beltwheel.

To these ends our invention consists in the novel construction and arrangement of parts hereinafter fully described and afterward definitely pointed out in the claims, due reference being had to the accompanying drawings, forming a part of this specification, wherein-'- Figure 1 is a front elevation of our improved device; Fig. 2, a side elevation of the same; and Fig. 3, a detail View of one of the bearings of the upper roller, partly in section.

In constructing our improved device we constructaframe consisting of fou r guide-rods A A, arranged in pairs, each pair being connected at top and bottom by cross-bars B B and the two pairs of guide-rods being connected at top and bottom by transverse crossbars 0 0, there being four such cross-bars, two at the top and two at the bottom of the frame. The ends of the guide-rods are screwthreaded, over which are screwed nuts D to securely hold the cross-bars in position. E E indicate bearing-blocks perforated at each end and fitting over the guide-rods A A, there being two such bearing-blocks, one to each pair of guide-rods. Each of said bearingblocks is centrally perforated to form a bearing fora shaft F, upon which is rigidly mounted a roller G. Coiled about the guide-rods A A and interposed between the bearing-blocks E and the cross-bars B are coiled springs H,

which constantly exert their force to raise up the said bearing-blocks and with them the roller G, as will more fully hereinafter ap pear. Upon each of the guide-rods A is loosely mounted a bearing-block I, each pair of said bearing-blocks upon their adjacent sides being provided with trunnions i, which project inwardly toward each other. J ournaled upon said trunnions are bearing-blocks J, which are recessed at opposite ends to fit over said trunnions, and said bearing-blocks J are centrally perforated to form bearings for a shaft K, upon which is rigidly mounted a roller L.

The cross-bars B are centrally apertured and screw-threaded to receive regulatingscrews M, which bear against the upper sides of the bearing-blocks J, for the purpose hereinafter described.

The idle roller L is preferably made of slightly-greater diameter at its center than at its ends, in order that the greatest tension will normally be upon the center of the belt.

The operation of our improved device is as follows: The device is rigidly secured in position at any suitable point and the belt passes between the rollers G and L. The springs H constantly force the roller G upward, thus maintaining a constant tension upon the belt and taking up the slack. By screwing down the regulating-screws M the tension of the springs is increased. If both screws M be screwed down equally upon the bearingblocks J, carrying the roller L, the tension will fall exactly upon the middle of the belt, because the said roller is slightly greater in diameter at the center than at the ends; but should the belt exhibit a tendency to run off one side of the belt-wheel then one of the screws M is screwed down, causing one end of the roller L to bear against the belt running over the roller G with greater force than the other end, causing the belt to run over to the opposite side of the belt-wheel. In order to permit either end of the rollerL to be thus depressed, the bearing-blocks J, in which said roller is journaled, are swiveled, as before described.

Having described our invention, what we claim is-- 1. In a belt-idler, the combination, with the frame consisting of the guide-rods and connecting cross-bars, of the roller G, having bearings loosely mounted upon said guiderods, coiled springs arranged upon said guiderods beneath said bearings, the roller L, journaled in bearings loosely mounted upon said guide-rods, and the regulating-screws M for forcing down said roller, substantially as described.

2. In a belt-idler, the combination, with the frame consisting of the guide-rods and connecting cross-bars, of the roller G, having bearings loosely mounted upon said guiderods, coiled springs I-I, arranged upon said guide-rods and resting against the under sides of said bearings, the roller L, journaled in bearings loosely mounted upon said guiderods and independently adjustable, and the regulating-screws M for adjusting said roller, substantially as described, and for the purpose specified.

3. The combination of the guide-rods A and cross-bars B B C 0, connecting said guiderods at top and bottom, the roller G, journaled in bearing-blocks E, loosely mounted upon said guide-rods, the coiled springs H, interposed between said bearingblocks and the cross-bars B',the roller L of greater diameter at its center than at its ends and journaled in bearings loosely mounted upon said guiderods and independently adjustable, and the regulating-screws M for adjusting said roller, substantially as described, and for the purpose specified.

4. The combination of the guide-rods A and cross-bars B B O C, connecting said guiderods at top and bottom, the roller G, journaled in bearing-blocks E, loosely mounted upon said guide-rods, coiled springs H interposed between said bearing-blocks and the cross-bars B, the rollerL of greater diameter at its center than at its ends and journaled in bearings J,swive1ed upon trunnions 2', carried by bearing-blocks I I, loosely mounted upon the guide rods, and the regulatingscrews M, bearing upon the upper sides of said bearings, substantially as described, and for the purpose specified.

In testimony whereof we have signed this specification in the presence of two subscribing witnesses.

ALEXANDER V. HALL. WILL. S. HOLMES. \Vitnesses:

L. S. MGCARTY, W. C. BIBER'ON. 

